Abrading device

ABSTRACT

An abrading device including at least two elongated abrading members and mounting means for connecting the members to a rotating drive means, such as an electric drill, which rotates the mounting means and thus the members to accomplish abrading. The mounting means supports each abrading member at a position offset from the axis of rotation of the mounting means for pivotal movement about an axis perpendicular to the axis of rotation such that when rotation of the mounting means occurs, the members pivot from a rest position to an abrading position. In a first embodiment the members are supported in slots in the mounting means and in a second embodiment the members are supported on ears carried on one surface of the mounting means.

Elite atent H91 Whitsett Jan.7,1975

[ ABRADING DEVICE [76] Inventor: Jack W. Whitsett, 936 Castile Ave.,

Coral Gables, Fla. 33134 [22 Filedz Sept. 10,1973

211 App]. No.: 395,971

[52] US. Cl 51/332, 15/236, 30/172 [51] Int. Cl B241) 9/02, B23d 79/08 L5 8 1Field0f Search 15/165, 169, 170, 172,

[56] References Cited UNITED STATES PATENTS 3,065,579 11/1962 Clark 51/331 FOREIGN PATENTS OR APPLICATIONS 368.580 2/1939 Italy 51/332 Primary Examiner-Othell M. Simpson Attorney, Agent, or Firm-Roylance, Abrams, Berdo & Kaul [57] ABSTRACT An abrading device including at least two elongated abrading members and mounting means for connecting the members to a rotating drive means, such as an electric drill, which rotates the mounting means and thus the members to accomplish abrading. The mounting means supports each abrading member at a position offset from the axis of rotation of the mounting means for pivotal movement about an axis perpendicular to the axis of rotation such that when rotation of the mounting means occurs, the members pivot from a rest position to an abrading position. In a first embodiment the members are supported in slots in the mounting means and in a second embodiment the members are supported on ears carried on one surface of the mounting means.

12 Claims, 10 Drawing Figures Patented Jan. 7, 1975 2 Sheets-Sheet l Patented Jan. 7, 1975 3,858,367

2 Sheets-Sheet 2 ABRADING DEVICE This invention relates to an abrading device and, more particularly, it relates to a device having at least two or more abrading members which are rotated by suitable means, such as an electric drill.

The device is to be used to abrade surfaces to remove some type of surface coating therefrom. These coatings may be paint, rust, scale, marine growth, or wallpaper. Additionally, the device is to be used to finish concrete surfaces.

The present invention is an improvement upon the invention disclosed in my [1.8. Pat. No. 3,662,424 which was issued on May 16, 1972, for a Scraping Device. The present invention provides for a plurality of abrading members pivotally supported on a spindle at a position which is offset from the axis of rotation of the spindle. The construction provides for numerous advantages over my previous scraping device.

Specifically, in the present invention, two radially opposed blades can be hard-faced chippers and two other radially opposed blades can be wire brushes which can provide both a chipping and dust removing action to a surface to be cleaned. Additionally, since the members are offset from the axis of rotation, the precession adjustment for the present invention is less than that of my previous invention. Furthermore, with the increased number of members or blades, the impact frequency with which the blades strike the surface to be cleaned is proportionally increased. Moreover, the addition of the spindle to the apparatus increases the inertia of the device and relieves certain amounts of shockloading from the motor shaft.

Another advantage is that, since the spindle support ing the blades is connected to a rotating drive means via a rigid rod, a precise and accurate abrading action is provided. In this regard, it is important to note that the device can be used to abrade such hard substances as concrete and that heavy pressure can be brought to bear on the blades, thereby increasing their abrading action. Further, since the blades are pivotally mounted at one end, the blade edges describe a conical surface during rotation. This provides both a chipping action when the rotating blades are forced against a surface and an automatic self-adjusting feature. That is, as the blade wears on its bottom edge, the centroid of the blade moves away from the edge, thereby causing the conical surface to spread out and allow a larger portion of the blades edge to come into an abrading contact with the surface to be abraded. This relieves the necessity of height adjustment of the blades.

It is therefore an object of the present invention to provide a new and improved abrading device.

Another object of the present invention is to provide an abrading device which can be used with a conventional rotating power supply, such as an electric drill, so that the abrading device can be made available at reasonable cost to the average homeowner.

Another object of the present invention is to provide a simple form of abrading device which is highly adaptable and versatile, yet which can be used with a minimum amount of manual effort.

Another object of the present invention is to provide a safe, comfortable and efficient abrading device which can be adapted to accomplish a variety of different sur face abrading operations.

The foregoing objects are attained by providing a spindle with a plurality of blades or abrading members which are pivotally mounted to the spindle at a position which is offset from the axis of rotation of the spindle. Each abrading member is an elongated blade having an abrading edge along one side thereof. Each abrading member has a transverse aperture passing therethrough at a position spaced from the abrading edge through which a bolt may pass to pivotally mount each abrading member to a spindle. In a first embodiment of the present invention the spindle has a plurality of slots passing completely therethrough and into which a portion of each abrading member is positioned for pivotal mounting. In the second embodiment a plurality of ears are welded to one surface of the spindle wherein each abrading member is pivotally mounted in a substantially radial direction by means of a bolt passing through a transverse aperture in each ear. Along the central axis of the spindle, means are provided for rigidly attaching the spindle to an electric drill which provides the drive means for rotating the spindle.

In operation, when the electric drill is activated, the spindle rotates and causes the pivotally mounted abrading members to pivot from a rest position to a position at which each abrading edge is at an angle of at least to the bottom surface of the spindle. To accomplish the abrading action the rotating abrading members are placed against the surface to be abraded.

Other objects, advantages, and salient features of the present invention will become apparent from the following detailed description which, taken in conjunction with the annexed drawings discloses two preferred embodiments thereof.

Referring now to the drawings which form a part of this original disclosure:

FIG. 1 is a bottom plan view of the device in accordance with the present invention;

FIG. 2 is a side elevational sectional view of the present invention taken along lines 2-2 of FIG. 1;

FIG. 3 is a perspective view of one of the abrading members;

FIG. 4 is a side elevational view of the device showing the abrading members at their rest position;

FIG. 5 is a side elevational view showing the device in accordance with the present invention connected to an electric drill and performing the abrading operation, with only two abrading members being illustrated for sake of clarity;

FIG. 6 is a top plan view of the device shown in FIG. 1 in operation;

FIG. 7 is a perspective view showing the bottom surface of a modified spindle used in the present invention;

FIG. 8 is a fragmentary view of the modified spindle showing one ear attached to the bottom surface and a modified abrading member associated therewith;

FIG. 9 is a sectional view taken along lines 9-9 of FIG. 7 and which additionally shows two of the modified abrading members attached to the modified spindle; and

FIG. 10 is a side elevational view of a wire brush which can be attached to either of the spindles shown in FIG. 1 or FIG. 7.

Referring now to the drawings in further detail, a typical form of the abrading device is shown in FIG. 1 and is generally designated 20. The abrading device includes a plurality of abrading members generally designated 22 and a mounting means generally designated 24.

As seen in FIGS. 1 and 2, the mounting means 24 includes a spindle 26 having an aperture 28 centrally located therein. As shown in FIG. 4, the spindle has a top planar surface 27 and a bottom planar surface 29. Welded to the sides of the aperture is the end of a solid bar 30 which has one end flush with the bottom surface of the spindle 26 and another end extending upwardly from the top surface of the spindle and having a centrally located threaded bore 32 therein. Equally radially spaced around the spindle are a plurality of slots 34 which extend from the periphery of the spindle towards the central aperture 28 but end at a position space from the aperture. Each of these slots 34 pass completely through the thickness of the spindle 26. As shown in FIG. 1 four such slots are provided, although more may be provided as necessary. Each one of the slots 34 receives a portion of one of the elongated abrading members 22.

As shown in FIGS. 1 and 2, each slot 34 has provided in a wall on one side a threaded blind bore 38 and in the opposite wall a threaded bore 40 which passes completely through that portion of the spindle 26 which defines the other side of the slot 34. A threaded screw or bolt 24 passes through each of the bores 38 and 40 to pivotally mount each abrading member 22 in each of the slots 34, as will be described hereinafter.

As shown in FIGS. 2 and 3, the abrading member 22 is in the form of a T-beam an includes an elongated rectangular bottom or blade portion 44 and an elongated rectangular top portion 46 which is integrally formed with or rigidly connected to the bottom portion at an angle of 90. As shown in FIG. 3, the top edge 43 of the bottom portion 44 is connected to the bottom of the top portion along the middle thereof. Located in the lower corner of the bottom portion 44 is a transverse aperture 48 which receives the threaded screw 42 to mount the abrading member 22 to the spindle 26 with the longer portion of the member extending outward from the screw mounting. Advantageously, the diameter of the threaded screw 42 is slightly smaller than the transverse aperture 48 which will allow the abrading member 22 to pivot around the threaded screw. The abrading member 22 can be formed of any suitable rigid metallic meterial, such as hard steel, and has at the bottom edge of the bottom portion 44 an abrading edge 50 which can be sharpened or coated with an abrasive material such as silicon carbide. As seen in FIG. 3, the bottom portion 44 has a first end 45 and a second end 47 located at opposite ends thereof. The first end 45 is closest to the bar 30 and the second end is farthest therefrom with the abrading edge 50 located therebetween on the bottom and the top edge 43 located therebetween on the top.

Although the abrading member 22 shown in FIG. 3 has a top portion 46, if desired, this can be eliminated so that the abrading member is merely comprised of the bottom rectangular portion 44. In other words, the inertia properties of the abrading member can be varied as desired. Furthermore, as set forth in my US. Pat. No. 3,662,424, the location of the transverse aperture 48 relative to the center line and centroid of each abrading member can be varied with a concomitant variation of the position of the pivoting axis provided to the abrading member. This, of course, will alter the angle to which the abrading member will move when the spindle is rotated.

As shown in FIG. 4, the spindle 26 is oriented in a plane which is horizontal and the abrading members 22 are in a rest position, such position being determined by the position of the transverse aperture 48. As there set forth, the diehdral angle between the abrading edge 50 on each abrading member and the surface 29 of the spindle 26 is less than 180.

As shown in FIG. 5, the present invention can advantageously be connected to an electric drill 60 toprovide the drive means for the spindle 26. Specifically, the electric drill 60 has a chuck 62 which receives one end of a connecting rod 64. The other end of the connecting rod can advantageously be threaded to coincide with and fit into the threaded bore 32 in the bar 30 which is in turn welded to the spindle 26.

In operation, on actuating the electric drill 60 the spindle 26 will be rotated at speeds of 2,000 to 3,000 rpm. Due to this rotation and the pivotal mounting of each abrading member 22 to the spindle 26, each abrading member 22 will pivot from its rest position shown in FIG. 4 to a dynamic position shown in solid lines in FIG. 5. This pivotal motion is due to centrifugal force acting on the abrading members. As shown in FIG. 5 the position of the transverse apertures in each of the abrading members taken together with the moments of inertia of each of the abrading members cause each member to assume a position which is at a diehdral angle greater than the angle in the rest position. This is the position in which the abrading members will remain unless a force acts to remove them from this position. Thus, when the abrading members 22 are placed against the surface 66 to be abraded and pressure is applied thereto the angle will increase to that shown in phantom in FIG. 5 or even to a larger angle depending on the pressure exerted. However, because the abrading members tend to stay in the position having a smaller angle, a chipping action will be provided to the surface 66. This enhances the abrading qualities of the present invention.

As shown in FIGS. 7, 8 and 9 a second embodiment in accordance with the present invention is presented. FIG. 7 shows a modified spindle generally designated 70 which is comprised of a circular plate 72 and a series of radially oriented and angularly spaced ears 74 welded to the bottom planar surface 75 of the plate.

The plate has a top planar surface 77 as seen in FIG.'

9. A centrally located aperture 76 in the plate 72 receives a bar 31 similar to bar 30 in the first embodiment for mounting the plate 72 to an electric drill 60 as described above.

Each ear 74 has a flat bottom edge 78 along which it is connected, such as by welding, to the planar surface 75 of the plate 72. Extending from the edge 78, each ear is substantially semi-circular and has a transverse aperture 80 passing completely through the thickness of each ear for the reception of a bolt 82 as shown in FIG. 8. In this embodiment a modified abrading member or blade 84 is formed as an elongated rod having a rectangular cross section and an abrading edge along its bottom edge. As seen in FIG. 9, each blade has, in addition to the bottom abrading edge 90, a first end 91, a second end 93 and a top edge 95. Each blade has a transverse mounting aperture 86 through which the bolt 82 may pass for pivotally securing each blade 84 to its respective ear 74 at a position between the first end 91 and the middle of the blade as shown in FIG. 8. A nut 88 secures each blade 84 to the bolt 82. Advantageously, each bolt is threaded only along a short portion at its free end to assure that the blade can pivot around the bolt.

As shown in FIGS. 7 and 9, each of the ears 74 is radially located at a position which is offset from the central aperture 76 and each blade 84 is connected at one end to each ear and can have its other end extend past the periphery of the plate 72. The position of the transverse mounting aperture 86 in each blade can be varied relative to the longitudinal centerline of each blade as shown in phantom in FIG. 8.

The operation of the second embodiment is similar to that of the first and, as shown in FIG. 9, in the rest position each blade 84 rests with its abrading edge 90 forming an angle less than 180 relative to the bottom surface of the plate 72. On rotation of the plate 72 by means of the electric drill, the blades 84 pivot upwardly under centrifugal forces as shown in phantom in FIG. 9 to an abrading position.

As shown in FIG. 7, six ears 74 can be used. However, if a greater or less number of blades are desired then a larger or smaller number of cars may be utilized. As shown in FIG. 10, the abrading members can also be formed as a wire brush having a rigid backing 92 of metal or the like and having a plurality of wire or steel bristles 94 projecting downward therefrom. The ends 96 of these bristles form the abrading edge for an abrading member of this type. In order to mount an abrading member of this type, a generally C-shaped plate 97 can be used, which plate is provided with a central aperture 98 disposed beneath the surface of the brush backing 92 so that a screw or bolt can extend therethrough to pivotally mount the brush to either of the spindles 26 or 72. Screws 99 can be used to attach the plate 97 to the backing 92. With the addition of this type of brading member both a chipping and brushing action can be exerted on the surface to be cleaned.

While certain advantageous embodiments have been chosen to illustrate the invention, it will be understood by those skilled in the art that various changes and modifications can be made therein without departing from the scope of the invention as defined in the ap pended claims.

What is claimed is: 1. An abrading device adapted for use in combination with a rotating drive means, said device comprismg:

at least two axially elongated abrading members, each comprising a blade portion having a first end, a second end, a top edge and an abrading edge;

mounting means, rigidly connected to and rotatable by said rotating drive means, for supporting said members,

said mounting means including means for freely supporting said members for pivotal movement at a position offset from the axis of rotation of said mounting means about fixed axes, each lying in a plane perpendicular to a plane containing said axis of rotation;

said mounting means having an axis of rotation coincident with the axis of rotation of said rotating drive means,

said means for freely supporting said members including rods secured to said mounting means along said axes, and

mounting apertures each located in one of said blade portions between said first end and the midpoint between said first and second ends, said mounting apertures each having a diameter larger than said rods and each of said rods passing through one of said apertures,

said means for freely supporting said members also supporting said abrading edges in non-coplanar planes when said drive means is not rotating, said edges forming with a plane containing said mounting means dihedral angles of less than 180;

said means for freely supporting said members also supporting said abrading edges at an angle to the plane of said mounting means which is greater than said dihedral angles when said rotating drive means is operated so said abrading edges describe a conical surface;

said device being operative to accomplish abrading by engaging at least a portion of said abrading edges against an object as said members rotate to thus cause said edges to abrade said object.

2. An abrading device according to claim I wherein said mounting means includes:

a spindle connected to said rotating drive means, said spindle having a top planar surface and bottom planar surface,

said spindle having a plurality of slots passing completely therethrough for partially receiving in each one of said abrading members.

3. An abrading device according to claim 1 wherein said mounting means includes:

a spindle connected to said rotating drive means, said spindle having a top planar surface and a bottom planar surface,

said spindle having a plurality of ears depending from the bottom surface thereof for pivotally mounting on each one of said abrading members.

4. An abrading device according to claim 1 wherein each of said abrading members is T-shaped in crosssection.

5. An abrading device according to claim 1,

wherein said mounting means includes a spindle having a plurality of slots passing completely therethrough, each slot partially receiving an abrading member therein, and a cylindrical bar rigidly mounted to said spindle; and

further including a rigid rod interconnecting said bar and said rotating drive means.

6. An abrading device according to claim 1 wherein said mounting means has top and bottom planar surfaces which are parallel and are perpendicular to the axis of rotation of said mounting means.

7. An abrading device according to claim 6 wherein said mounting means further includes means defining at least two slots therein, each for partially receiving one of said abrading members, said slots extending in radial directions relative to said axis of rotation of said mounting means.

8. An abrading device according to claim 7 wherein said slots are diametrically opposed relative to said mounting means axis of rotation.

9. An abrading device according to claim 1 and including four axially elongated abrading members supported by said mounting means at intervals about said axis of rotation of said mounting means.

12. An abrading device according to claim 1 wherein said mounting means comprises a spindle having top and bottom planar, circular surfaces, and

said means for freely supporting said members further includes at least two cars rigidly coupled to said spindle bottom surface, each ear having an aperture therein receiving said rods. 

1. An abrading device adapted for use in combination with a rotating drive means, said device comprising: at least two axially elongated abrading members, each comprising a blade portion having a first end, a second end, a top edge and an abrading edge; mounting means, rigidly connected to and rotatable by said rotating drive means, for supporting said members, said mounting means including means for freely supporting said members for pivotal movement at a position offset from the axis of rotation of said mounting means about fixed axes, each lying in a plane perpendicular to a plane containing said axis of rotation; said mounting means having an axis of rotation coincident with the axis of rotation of said rotating drive means, said means for freely supporting said members including rods secured to said mounting means along said axes, and mounting apertures each located in one of said blade portions between said first end and the midpoint between said first and second ends, said mounting apertures each having a diameter larger than said rods and each of said rods passing through one of said apertures, said means for freely supporting said members also supporting said abrading edges in non-coplanar planes when said drive means is not rotating, said edges forming with a plane containing said mounting means dihedral angles of less than 180*; said means for freely supporting said members also supporting said abrading edges at an angle to the plane of said mounting means which is greater than said dihedral angles when said rotating drive means is operated so said abrading edges describe a conical surface; said device being operative to accomplish abrading by engaging at least a portion of said abrading edges against an object as said members rotate to thus cause said edges to abrade said object.
 2. An abrading device according to claim 1 wherein said mounting means includes: a spindle connected to said rotating drive means, said spindle having a top planar surface and bottom planar surface, said spindle having a plurality of slots passing completely therethrough for partially receiving in each one of said abrading members.
 3. An abrading device according to claim 1 wherein said mounting means includes: a spindle connected to said rotating drive means, said spindle having a top planar surface and a bottom planar surface, said spindle having a plurality of ears depending from the bottom surface thereof for pivotally mounting on each one of said abrading members.
 4. An abrading device according to claim 1 wherein each of said abrading members is T-shaped in cross-section.
 5. An abrading device according to claim 1, wherein said mounting means includes a spindle having a plurality of slots paSsing completely therethrough, each slot partially receiving an abrading member therein, and a cylindrical bar rigidly mounted to said spindle; and further including a rigid rod interconnecting said bar and said rotating drive means.
 6. An abrading device according to claim 1 wherein said mounting means has top and bottom planar surfaces which are parallel and are perpendicular to the axis of rotation of said mounting means.
 7. An abrading device according to claim 6 wherein said mounting means further includes means defining at least two slots therein, each for partially receiving one of said abrading members, said slots extending in radial directions relative to said axis of rotation of said mounting means.
 8. An abrading device according to claim 7 wherein said slots are diametrically opposed relative to said mounting means axis of rotation.
 9. An abrading device according to claim 1 and including four axially elongated abrading members supported by said mounting means at 90* intervals about said axis of rotation of said mounting means.
 10. An abrading device according to claim 9 wherein said elongated abrading members are supported by said mounting means radially of said axis of rotation of said mounting means.
 11. An abrading device according to claim 1 and including four abrading members, two of which have bristles extending from said abrading edges.
 12. An abrading device according to claim 1 wherein said mounting means comprises a spindle having top and bottom planar, circular surfaces, and said means for freely supporting said members further includes at least two ears rigidly coupled to said spindle bottom surface, each ear having an aperture therein receiving said rods. 